I recently switched from a Linksys router that was having trouble to a Vonage VPortal router. Soon after it started having issues where my phone calls would drop and my internet connection would get slower and slower. After rebooting the router it would go back to normal. Removing the router out of the loop would give me a great internet connection on my Comcast cable modem with no issues. I called technical support and they did something that got it working for about a month. Now it is doing the same thing. Any ideas? Is this a known problem?

Not sure that I have heard others complain about that exact issue. You can use the VPortal as simply an ATA and not a router. You can purchase a new Linksys and plug that into your cable/dsl device and then plug the VPortal into the Linksys and provide the QoS control through the LInksys interface. This in essence dumb down your Vportal so that its only function is to service the telephone.